That hoary issue of when it is safe to leave your children at home alone has raised its head again, after Simten Sadiq, a 33-year-old mother of three, apparently left her children at home in Leeds for a fortnight.

While Sadiq seemed to have spent some time on honeymoon in Afghanistan with her new Austrian husband, her children Amira, 11, Saarah, 6, and Mohammed, 5, looked after themselves and lived on the food that their mother had left them.

A neighbour was reported as saying that he saw them playing and that they were “very well turned out and groomed as always”, while another noticed no adult present and called the police. Sadiq - who is believed to have arranged for a female relative to keep an eye on her son and daughters - was arrested on suspicion of “wilful neglect” and released on bail, pending further inquiries. The children have been placed in temporary foster care.

Most parents know that however mature their 11-year-old is, they should not burden her with such responsibility for longer than an afternoon, let alone a fortnight. But what is the law regarding leaving your child at home alone? How old must a child be to look after younger siblings and, more importantly, what constitutes neglect? Is it really so wrong, for instance, to nip across the road for a pint of milk or to post a letter while your one-year-old is sound asleep in her cot?

In 1918 D.H. Lawrence published an essay entitled Education of the People, insisting that benign neglect should be a priority when bringing up your child. “How to begin to educate your child. First rule: leave him alone. Second rule: leave him alone. Third rule: leave him alone. That is the whole beginning,” he wrote.

The Children and Young Persons Act, 1933, stated that parents could be prosecuted for wilful neglect only if they left a child unsupervised “in a manner likely to cause unnecessary suffering or injury to health”. That would include leaving a child alone for long periods, or not feeding or clothing him or her adequately.

In the eyes of the law there is no official minimum age at which a child may be left at home or in charge of siblings. Nor, for that matter, is there a minimum age for a babysitter (although the NSPCC recommends 16); it is up to parents to decide.

Many people agree that this is a grey area which should not be legislated upon: one family's nine-year-old may be far more mature than another's 12-year-old; should you really be prosecuted for leaving him or her while you sneak off for a coffee? But, as a rule of thumb, no child at primary school should ever be “left in charge” for longer than an hour or two.

Yet for many people this lack of clarity is confusing, says Eileen Hayes, the NSPCC's parenting adviser. “I once left my baby in the car for a brief time and when I came back, a policeman was waiting for me,” she says. “It's not illegal but it was embarrassing, and if anything had happened I'd have been done for neglect.

“The NSPCC says you should never leave a baby on his own because of that one-in-a-thousand chance of the car rolling away, or the washing machine catching fire while you're out of the house. But in the end you weigh the risks.”

The Sadiq case is by no means an isolated one, Hayes says, and parents often get away with nipping out to the pub for a swift pint when the children are asleep, or even going away for a weekend, unless the police are informed. But while a five-year-old may be able to dress on his own, or be comforted by his older sister if he wakes at night, he will still wonder where Mummy is. Above all, she says, it is unfair to make one young child responsible for another, especially if an accident occurs.

Honor Rhodes, director of development at the Family and Parenting Institute, agrees. “So much depends on the child. But there's a difference between leaving your 12-year-old in charge of the younger ones when you do the supermarket shop and leaving them while you're out at a dinner party,” she says. “Probably everything will be fine, but if it's not then the older child will have to live with the guilt for the rest of his or her life.”

The trickier issue, Rhodes says, is when children become young adults and refuse to accept a babysitter. According to the National Childminding Association's latest study, just 7 per cent of carers look after children aged 12 and over. At that point, parents must ask their stroppy teenagers to demonstrate their readiness to be left, and be certain that they will know what to do in an emergency.

“Ask them to show you how they could cope on their own. If they want to be treated like an adult, let them show you that they can operate the oven safely, empty the dishwasher and fill the washing machine,” says Rhodes.

If leaving your children at home unsupervised is fraught with difficulty, can we ever risk leaving them asleep with the monitor on in a foreign hotel? The memory of Madeleine McCann will remain with parents of young children for decades, says Rhodes.

“People are much more nervous on holiday now - but in Britain we value our time away from our babies, so we live with monitors. It is highly unlikely that anyone would break into a hotel room, and if your child is a light sleeper and you can get back to her in minutes you might take that risk,” she says. “But if you don't take her, you may spend all of dinner worrying.”

If you really want to spend an evening away from your children without having shipped them out to grandparents or friends, it is worth recalling the sobering experience of the McGuckin family.

In May, the three children of Eamon and Antoinette McGuckin, from Co Londonderry, were taken into temporary care in Portugal when their mother collapsed one night. Police accused her of binge-drinking, but the McGuckins insisted that Antoinette had become violently ill and that her husband had arranged for the children to be looked after before taking her to hospital.

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